FBA user management search performance issues

We use the SP2010 FBA pack on an Intranet solution we built for one of our clients.
During development and internal test we had 10s-100s of users and found no issues with the FBA pack, however our client has 1000s of users and have reported performance issues with the user management page, in particular initial page loads and searching for
users.

I've had a dig through the code and think the poor performance is due to the code retrieving all users when searching and then applying the filter in memory (i.e not passing the search parameters to the SPQuery). Are there any plans to improve this functionality?
We've seen the page take up to 20 seconds to load when using in the region of 3,000 users.

This is true, and it's definitely on the todo list of things to improve. I just have to find the time to do it. There are some definite issues though - the reason they are all retrieved before searching is because the data that needs to be searched is
a combination of data from SharePoint and from the membership database. Additionally, the membership provider doesn't provide functions for doing partial searches - so if we did the partial searches directly against the database it would prevent the FBA Pack
from being compatible with custom membership providers.

We have a similar issue with a custom user management page that we wrote.
We search using the membership database first, however as we allow them to search by SP group we have to filter further by group in memory.